1. Field of the Invention
The present invention relates to audio entertainment systems, and more particularly, to a composite entertainment and public address system exhibiting improved information transfer characteristics.
2. Description of the Prior Art
Many systems are presently available for providing background music and for enabling the selective interruption of music for the purpose of playing messages, announcements and the like. Such systems are found in hotels, hospitals and other fixed installation but have had only limited application on Mass Transit vehicles although modern Mass Transit vehicles are equipped with Public Address Systems, for the announcements of station stops and emergency instructions, that would be well adapted for the carrying of music, commercials, etc.
Two main problems have prevented Transit companies from realizing the benefits of the entertainment programs that could be carried. First, because of the high electrical noise levels generated by the electrical propulsion systems of modern transit cars and because such vehicles frequently travel in tunnels and between metallic structures, high quality radio reception is impossible. Secondly, since it is necessary that station and emergency announcements make frequent priority interruptions on the program, present techniques do not permit the uninterrupted transmission of information; that is, a commerical or news announcement could be lost by a necessary station announcement and cause dissatisfaction to both riders and advertisers. My invention deals with and provides satisfactory solution to both problems.